Present communication techniques using radiofrequency (RF) suffer from a number of problems. First, there are security concerns because transmissions using RF can be easily intercepted, in part because of the fact that RF signals are designed to radiate signals in all directions. Second, the heavy regulation by the Federal Communications Commission (FCC) and its control of the frequencies that may be used for RF transmission often present daunting challenges to RF broadcasters. Third, RF by its very nature is susceptible to interference and produces noise.
In contrast to RF communications, light sources used for communication are extremely secure due to the fact that they are focused within a narrow beam, requiring placing equipment within the beam itself for interception. Also, because the visible spectrum is not regulated by the FCC, light sources can be used for communications purposes without the need of a license. And, light sources are not susceptible to interference nor do they produce noise that can interfere with other devices.
Light emitting diodes (LEDs) can be used as light sources for data transmission, as described in U.S. Pat. Nos. 6,879,263 and 7,046,160, the entire contents of each being expressly incorporated herein by reference. LEDs have quick response to “ON” and “OFF” signals, as compared to the longer warm-up and response times associated with fluorescent lighting, for example. LEDs are also efficient in producing light, as measured in lumens per watt. Recent developments in LED technology, such as high brightness blue LEDs, which in turn paved the way for white LEDs, have made LEDs a practical alternative to conventional light sources. As such, LED technology provides a practical opportunity to combine lighting and communication. This combination of lighting and communication allows ubiquitous light sources such as street lights, home lighting, and office building lighting, for example, to be converted to, or supplemented with, LED technology to provide for communications while simultaneously producing light for illumination purposes.
Regarding office buildings, building management is a complex science which incorporates and governs all facets of human, mechanical and structural systems associated with buildings. As a result of the complexity, most commercial buildings are managed by commercial property management companies with great expertise. Both at the time of construction and throughout the life-cycle of a building, the interrelationships between people and the mechanical and structural systems are most desirably evaluated. Where possible and cost-effective, human interactions with a building and associated mechanical systems will be optimized, in turn providing the greatest benefit to both the owners and those who use the facilities afforded by the building. Noteworthy is the fact that building users may include both regular occupants such as individual or commercial tenants, and also transient occupants such as visitors, guests, or commercial customers.
Building management includes diverse facets, some which are simply representations of the building and associated systems and people, and other facets which are tangible. Exemplary of representations are accounting or financial monitoring responsibilities which will including record keeping control and assurance of financial transactions involving tenants, owners, and service providers. Exemplary of the physical or tangible responsibilities are physical development and maintenance, including identification of need for features, improvements, maintenance and the assurance of the execution of the same. As is well understood by those highly versed in building management, the diverse responsibilities and extent of information required to manage a building is often quite overwhelming.
One very important area associated with building management is lighting or illumination. While often perceived as a simple task of providing lights, this seemingly simple task has much research and science behind a well-designed lighting system. This is because safety, productivity and general well-being of occupants depend heavily on proper lighting.
Many factors need to be considered at the time of construction or remodeling to facilitate proper lighting design. Intended usage of a space is important in illumination design consideration, since this will dictate necessary illumination levels, times and duration of use, and anticipated cycling of the illumination. In other words, a supply closet will not ordinarily be designed for around-the-clock illumination, and may instead by configured to operate on a switch, or alternatively a motion detector with relatively short-delay turn-off when no motion is detected. The use of appropriate switches and motion detectors helps to reduce the energy required for a building to function with occupants, and simultaneously increases the life of many illumination components such as light sources (light bulbs and equivalents thereto) since the light sources are only required intermittently. As another example, a room where movies, slides, computer or other visual or audio-visual presentations are given, such as a boardroom or classroom, will preferably have light controls such as separate switches or switches and dimmer controls which enable the entire room to be well lit or alternatively maintain a minimum level of illumination normally opposite to where the presentation is displayed. This minimum level of illumination enables occupants sufficient light for note-taking, safe movement and other important activities, without interfering with the legibility of a presentation. In yet another example, a primary work-space such as a desk or kitchen counter will require illumination that does not cast shadows on the work space while work is being performed. Complementary illumination, such as windows or skylights, is also important in design consideration.
Nearly all public buildings rely on a great many lamps positioned throughout the interior of the building, such as along hall corridors and in each room, and also about the exterior. These lights have historically been activated manually, though more recently, a small but growing number are activated according to occupancy, proximity or motion sensors, typically incorporating the well-known Infra-Red (IR) motion sensors. Architects are commonly employed to assist not only with a floor plan of physical spaces, but also with the proper selection and layout of lighting to best complement the floor plan and usage of each space within a building. As may be appreciated, illumination of a space is determined at the time of production of blueprints, in anticipation of construction. The illumination that has been chosen for a space is essentially fixed during building construction. Changes may be made later, but not without substantial additional expense that will, for exemplary purposes, often include removal of parts of or entire walls, with the accompanying disruption of the space. Often the space is unavailable for use during the entire duration of a remodeling project.
Further complicating the issue of illumination is the type of light bulb that may be most appropriate for a space or location. Original electric light bulbs were incandescent. With sufficient electrical energy, which is converted to heat within an incandescent bulb filament, the filament will emit visible light. This is similar to a fire, where with enough heat, visible light is produced. As might also be appreciated though, incandescent bulbs produce far more heat than light. The color of the light from these bulbs is also most commonly quite yellow, casting a warm hue at a color temperature typically in the vicinity of 3,000 degrees Kelvin. Warm hues are often prized in relaxed settings such as those of a living room or dining room, more closely resembling gentle candle light. However, in contrast thereto, work and study environments are more preferably illuminated with light of more blue content, more closely resembling daylight with color temperatures of approximately 6,000 degrees Kelvin. Daylight color temperatures are not practically obtained using an incandescent bulb. In addition, these incandescent bulbs have only a few thousand hour life expectancy, even with more than a century of improvements, because the extreme temperatures required for the filament to light also gradually evaporates the filament material. Finally, the thermal mass of the filament greatly influences how quickly the filament both illuminates and extinguishes. In spite of the many limitations, incandescent bulbs are still in fairly wide-spread use today.
An alternative to incandescent light bulbs in common use today is the fluorescent bulb. A fluorescent light bulb uses a small amount of mercury in vapor state. High voltage electricity is applied to the mercury gas, causing the gas to ionize and generate some visible light, but primarily Ultraviolet (UV) light. UV light is harmful to humans, being the component that causes sun burns, so the UV component of the light must be converted into visible light. The inside of a fluorescent tube is coated with a phosphorescent material, which when exposed to ultraviolet light glows in the visible spectrum. This is similar to many glow-in-the-dark toys and other devices that incorporate phosphorescent materials. As a result, the illumination from a fluorescent light will continue for a significant time, even after electrical power is discontinued, which for the purposes of the present disclosure will be understood to be the latent period or latency between the change in power status and response by the phosphor. As the efficiencies and brightness of the phosphors has improved, so in many instances have the delays in illumination and extinguishing, or latency, increased. Through the selection of many different modern phosphorescent coatings at the time of manufacture, fluorescent bulbs may be manufactured that produce light from different parts of the spectrum, resulting in manufacturing control of the color temperature, or hue or warmness of a bulb.
The use of fluorescent bulbs, even though quite widespread, is controversial for several reasons. One source states that all pre-1979 light ballasts emit highly toxic Polychlorinated BiPhenyls (PCBs). Even if modern ballasts are used, fluorescent bulbs also contain a small but finite amount of mercury. Even very small amounts of mercury are sufficient to contaminate a property. Consequently, both the manufacture and disposal of mercury-containing fluorescent tubes is hazardous. Fluorescent lighting has also been alleged to cause chemical reactions in the brain and body that produce fatigue, depression, immuno-suppression, and reduced metabolism. Further, while the phosphor materials may be selected to provide hue or color control, this hue is fixed at the time of manufacture, and so is not easily changed to meet changing or differing needs for a given building space.
Other gaseous discharge bulbs such as halide, mercury or sodium vapor lamps have also been devised. Halide, mercury and sodium vapor lamps operate at higher temperatures and pressures, and so present undesirably greater fire hazards. In addition, these bulbs present a possibility of exposure to harmful radiation from ruptured outer bulbs that go undetected. Furthermore, mercury and sodium vapor lamps generally have very poor color-rendition-indices, meaning the light rendered by these bulbs is quite different from ordinary daylight, distorting human color perception. Yet another set of disadvantages has to do with the starting or lighting of these types of bulbs. Mercury and sodium vapor lamps both exhibit extremely slow starting times, often measured by many minutes. The in-rush currents during starting are also commonly large. Many of the prior art bulbs additionally produce significant and detrimental noise pollution, commonly in the form of a hum or buzz at the frequency of the power line alternating current. In some cases, such as fluorescent lights, ballasts change dimension due to magnetostrictive forces. Magnetic field leakage from the ballast may undesirably couple to adjacent conductive or ferromagnetic materials, resulting in magnetic forces as well. Both types of forces will generate undesirable sound. Additionally, in some cases a less-optimal bulb may also produce a buzzing sound.
When common light bulbs are incorporated into public and private facilities, the limitations of existing bulb technologies often will adversely impact building occupants. As just one example, in one school the use of full-spectrum lamps in eight experimental classrooms decreased anxiety, depression, and inattention in students with SAD (Seasonal Affective Disorder). The connection between lighting and learning has been conclusively established by numerous additional studies. Mark Schneider, with the National Clearinghouse for Educational Facilities, declares that ability to perform requires “clean air, good light, and a quiet, comfortable, and safe learning environment.” Unfortunately, the flaws in much of the existing lighting have been made worse as buildings have become bigger. The foregoing references to schools will be understood to be generally applicable to commercial and manufacturing environments as well, making even the selection of types of lights and color-rendition-indexes very important, again depending upon the intended use for a space. Once again, this selection will be fixed, either at the time of construction when a particular lighting fixture is installed, or at the time of bulb installation, either in a new fixture or with bulb replacements.
A second very important area associated with building management is energy management. The concern for energy management is driven by the expense associated with energy consumed over the life of a building. Energy management is quite challenging to design into a building, because many human variables come into play within different areas within a building structure. Considering the foregoing discussion of lighting, different occupants will have different preferences and habits. Some occupants may regularly forget to turn off lights when a space is no longer being occupied, thereby wasting electricity and diminishing the useful life of the light bulbs. In another instance, one occupant may require full illumination for that occupant to operate efficiently or safely within a space, while a second occupant might only require a small amount or local area of illumination. Further complicating the matter of energy management is the fact that many commercial establishments may have rates based upon peak usage. A business with a large number of lights that are controlled with a common switch may have peak demands large relative to total consumption of power, simply due to the relatively large amount of power that will rush in to the circuit. Breaking the circuit into several switches may not adequately address inrush current, since a user may switch more than one switch at a time, such as by sliding a hand across several switches at once. Additionally, during momentary or short-term power outages, the start-up of electrical devices by the power company is known to cause many problems, sometimes harming either customer equipment or power company devices. Control over inrush current is therefore very desirable, but not economically viable in the prior art.
Energy management also includes consideration for differences in temperature preferred by different occupants or for different activities. For exemplary purposes, an occupant of a first office space within a building may prefer a temperature close to 68 degrees Fahrenheit, while a different occupant in a second office space may prefer a temperature close to 78 degrees Fahrenheit. The first and second office spaces may even be the same office space, just at different times of day. For exemplary purposes, an employee working in a mail room from 8 a.m. until 4 p.m. may be replaced by a different mail room employee who works from 4 p.m. until 12 a.m. Heating, Ventilation, and Air Conditioning (HVAC) demand or need is dependent not only upon the desired temperature for a particular occupant, but also upon the number of occupants within a relatively limited space. In other words, a small room with many people will require more ventilation and less heating than that same room with only one occupant.
With careful facility design, considerable electrical and thermal energy can be saved. Proper management of electrical resources affects every industry, including both tenants and building owners. In the prior art, this facility design has been limited to selection of very simple or basic switches, motion detectors, and thermostats, and particular lights, all fixed at the time of design, construction or installation.
A third very important area associated with building management is security. Continuing to use a school as but one example of a public building, a one-room country school fifty years ago was made up of one teacher who knew well the small number of pupils. Security consisted of a simple padlock on a wooden door. The several windows on one side of the room provided light. They were locked but almost never broken into, for nothing of major value, even during the Depression, enticed potential thieves.
Architecture changed as the years passed. Buildings were enlarged as school populations increased. Students started to conceal books, outerwear, valuables, and occasionally even weapons in enclosed lockers. Indoor lighting was required. Eventually as society became more hazardous, security had to be provided in many schools in the form of personnel who were required to patrol both outside and inside schools in order to provide a measure of safety.
In many public buildings, including schools, modern security presently screens a building's occupants to ensure that they belong or have proper authorization to enter the building. Security must also check for weapons, drugs, and even explosives. Thus, modern security personnel are often responsible for property as well as people. As the types of potential perils increase, so does the need for personnel, to process occupants through more and more stations. For exemplary purposes, in schools, airports, court houses, and other public facilities, one or more guards may check identification, admission badges or paperwork, while one or more other guards monitor metal detectors. One or more additional guards may be monitoring drug sniffing dogs or equipment, or spot checking bags. Unfortunately, the possibilities of duplication and/or forgery of credentials, or of hostile powers infiltrating security, or other criminal methods demonstrate the potential weaknesses of the present system, which depends upon a large number of security employees. Motion sensors and other prior art electronic security measures, while often beneficial, occasionally fail even when used in combination with security personnel to provide adequate protection. On the outside of a building, motion sensors may be activated by strong winds, stray animals, passing vehicles, or blowing debris. Inside, they operate only for a specific time; a room's occupant, if not moving about, may suddenly be in the dark and must re-activate the light by waving or flailing about.
An increasingly complex, and therefore hazardous, society requires increasingly extensive patrols and safeguards. Current security system, which must rely on increasing the numbers of guards and security devices, are subject to inherent defects and extraordinary expense, generally rendering them inadequate even with the best of intention.
Yet another very important area associated with building management is guidance control and indication, which impacts building security, as well as building convenience and efficiency for occupants. In buildings having many alternative hallways or paths, such as are commonly found in hospitals and other large public facilities, directions are often clumsy and difficult for visitors or emergency personnel to follow. Old-fashioned directories may be hard to locate or decipher, especially for non-English speakers or for persons with little or no time, again such as emergency personnel. Consequently, some buildings provide color stripes along walls that serve as color coding to guide visitors to various areas within the building. Unfortunately, the number of color stripes that may be patterned is quite limited, and the expense and defacing of appearance associated therewith is undesirable. Furthermore, such striping does not completely alleviate confusion, and the color stripes can only serve as general guides to commonly visited areas.
In addition to their numerous uses with building management, LEDs can be used in networking applications. In any network, a variety of client devices will communicate with one or more host devices. The host may provide connection to a Local Area Network (LAN), sometimes referred to as an Intranet, owing to the common use of such a network entirely within an office space, building, or business. The host may additionally or alternatively provide connection to a Wide Area Network (WAN), commonly describing a network coupling widely separated physical locations which are connected together through any suitable connection, including for exemplary purposes but not solely limited thereto such means as fiber optic links, T1 lines, Radio Frequency (RF) links including cellular telecommunications links, satellite connections, DSL connections, or even Internet connections. Generally, where more public means such as the Internet are used, secured access will commonly separate the WAN from general Internet traffic. The host may further provide access to the Internet.
A variety of client devices have heretofore been enabled to connect to host devices. Such client devices may commonly include computing devices of all sorts, ranging from hand-held devices such as Personal Digital Assistants (PDAs) to massive mainframe computers, and including Personal Computers (PCs). However, over time many more devices have been enabled for connection to network hosts, including for exemplary purposes printers, network storage devices, cameras, other security and safety devices, appliances, HVAC systems, manufacturing machinery, and so forth. Essentially, any device which incorporates or can be made to incorporate sufficient electronic circuitry may be so linked as a client to a host.
Existing client devices are designed to connect to host network access points through wired connections, like copper wire, for example, fiber optic connections, or as wireless connections, such as wireless routers. In the case of a wired system, whether through simple wire, twisted wire, co-axial cable, fiber optics or other line or link, the host and client are tethered together through this physical communications channel. The tether, as may be appreciated, limits movement of the client relative to the host, is often unsightly and hard to contain in a workspace, and so may even be or become a tripping hazard. In addition, electrical connectors such as jacks must be provided, and these connectors necessarily limit the number of access points and locations. The installation of connectors defaces walls, sometimes rendering them unsuitable for a particular desired application, and yet they add undesirable installation expense, whether during new construction or in retrofitting an existing building structure.
In contrast, in the case of wireless routers, an RF signal replaces the physical communications channel with a radio channel. This advantageously eliminates the wire or fiber tether between client and host. Instead, client devices in a wireless system try through various broadcasts and signal receptions to find an access point that will have adequate transmission and reception, generally within a certain signal range which may range from a few meters to as many as several tens of meters. The systems are programmed to bridge from a host access point to various client devices through known exchanges of information, commonly described as communications protocols or handshakes. Depending upon the communications channel, a variety of client connection devices are utilized such as PCMCIA or PC cards, serial ports, parallel ports, SIMM cards, USB connectors, Ethernet cards or connectors, FireWire interfaces, Bluetooth compatible devices, infrared/IrDA devices, and other known or similar components.
The security of these prior art wireless devices can be compromised in that they are vulnerable to unauthorized access or interception, and the interception may be from a significant distance, extending often well beyond physical building and property boundaries. Moreover, reliability can be hindered by interference from an appliance such as a microwave oven.
Buildings can encompass a very large number of rooms or discrete spaces, each functioning relatively independently from each other. Where the rooms or discrete spaces together form a larger entity such as a business, public institution or facility, or the like, which have attempted to include synchronized time keeping throughout the entity. A large number of buildings, both public and private, have synchronized clocks installed therein.
These same buildings also have a number of additional features including, for exemplary purposes though not limited thereto, fire and smoke detection, temperature control, and public address. Because of the ever-changing nature of a building and the best practices associated therewith, it can be quite difficult if not impossible to keep all areas within a building up to date with best practices or preferred capabilities. One method of desirable features or capabilities within a building space is through the use of electrical wiring adequate to accommodate the features or capabilities, particularly when the features or capabilities are identified subsequent to original construction.
For exemplary purposes, a building may accommodate very different numbers of occupants at different times within a relatively enclosed space, such as a meeting or class room. The number of occupants is known to significantly alter the temperature and associated need for HVAC control. Furthermore, other factors, such as weather conditions and sunlight or lack thereof through windows in a room may have as much or greater effect on the need for HVAC control. However, many older buildings were only provided with a single central thermostat, providing the same amount of heating or air conditioning to a room or other space regardless of demand for the same. Newer HVAC systems enable control, through electrically controlled dampers or vents within the HVAC system to much more precisely respond to the needs of a single space or room within a building. However, without providing wiring within the room to accommodate the thermostat and various duct controls, the room may not be individually controlled.
Even where a building is originally provided with appropriate wiring for each electrical system or component desired, necessary remodeling may critically alter the need. As one example, consider when a room or space is subdivided into two smaller spaces. Existing wiring only provides for electrical connection to one set of devices for one room. In this case, it may be necessary to run new wires back to one or more central locations, utility rooms, or the like to accommodate the new room and devices within the room.
More buildings are incorporating wireless networks within the building, the networks which are intended to reduce the need for wiring alterations and additions practiced heretofore. However, these wireless networks are not contained within the walls of a building, and so they are subject to a number of limitations. One of these is the lack of specific localization of a signal and device. For exemplary purposes, even a weak Radio-Frequency (RF) transceiver, in order to communicate reliably with all devices within a room, will have a signal pattern that will undoubtedly cross into adjacent rooms. If only one room or space in a building is to be covered, this signal overlap is without consequence. However, when many rooms are to be covered by different transceivers, signal overlap between transceivers requires more complex communications systems, including incorporating techniques such as access control and device selection based upon identification. Since the radio signal is invisible, detection of radiant pattern and signal strength are difficult and require special instruments. Further, detection of interference is quite difficult. Finally, such systems are subject to outside tapping and corruption, since containment of the signal is practically impossible for most buildings.
Another issue associated with use of conventional and LED lighting sources concerns the difficulty in quantifying the amount of use of a light source, as well as the amount of degradation or exhaustion of a light source before light source failure.
All U.S. patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.